Retrograde sorting

Question

I am looking for a way how to transfer this (and similar) block of text:

dollar_value: str = field(init=False)
dollar_symbol: str = field(init=False)
dollar_unit: str = field(init=False)
euro_value: str = field(init=False)
euro_symbol: str = field(init=False)
euro_unit: str = field(init=False)
bitcoin_value: str = field(init=False)
bitcoin_symbol: str = field(init=False)
bitcoint_unit: str = field(init=False)
ether_value: str = field(init=False)
ether_symbol: str = field(init=False)
ether_unit: str = field(init=False)
litecoin_value: str = field(init=False)
litecoin_symbol: str = field(init=False)
litecoin_unit: str = field(init=False)

into this

dollar_value: str = field(init=False)
euro_value: str = field(init=False)
bitcoin_value: str = field(init=False)
ether_value: str = field(init=False)
litecoin_value: str = field(init=False)
dollar_symbol: str = field(init=False)
euro_symbol: str = field(init=False)
bitcoin_symbol: str = field(init=False)
ether_symbol: str = field(init=False)
litecoin_symbol: str = field(init=False)
dollar_unit: str = field(init=False)
euro_unit: str = field(init=False)
bitcoint_unit: str = field(init=False)
ether_unit: str = field(init=False)
litecoin_unit: str = field(init=False)

I though maybe in this particular case a retrograde sorting macro would be helpful (like normal sorting, but starting with the last letter of the word or line, progressing towards the first letter.

Is there a way to do retrograde sort in vim? Or what would be a possible approch to this?

Answer 1

Vim's :sort command can take an optional regex to indicate where to start sorting.

From :help :sort:

When /{pattern}/ is specified and there is no [r] flag the text matched with {pattern} is skipped, so that you sort on what comes after the match.

So this should be enough to sort lines, considering the text coming after the underscore:

:sort /_/

The sort is stable, so it will sort all "symbols", followed by all "units" and then all "values", preserving their relative order, which is the expected result you wanted.

It seems you wanted "values" first, but that should be a simple operation of cutting them from the end of the list and pasting them back at the beginning, getting to exactly the result you wanted.